Instead of only having the option to select a single key or time signature or random all key/time signatures, users would like the option to create a custom set of key or time signatures from which would be randomly picked each time an exercise was generated.
Hi Jeff, it is already in the iOS app. You may need to update your app if you aren't using the latest version. In order to use it in the iOS app, you will first need to go to your Dashboard via the website (in a web browser) and enable this feature on the preferences tab. You will see options to select multiple key and time signatures. Let me know if you have any problems accessing the feature in the iOS app!
This is now implemented!